[Note: Oxidative stress/free radical damage to cells results from an imbalance between products of oxidation and antioxidant defenses. The authors note it is increased in patients with ME/CFS.]

Oxidative stress is thought to play a role in the pathogenesis of fibromyalgia. We examined the hypothesis that oxidative stress was increased in patients with fibromyalgia and related to the severity of symptoms.

Urinary F(2)-isoprostane excretion was measured in 48 patients with fibromyalgia and compared to those of 96 control subjects. In patients, we examined the association between oxidative stress and symptoms.